Structure cristalline du compose intermetallique Ni18Ge12.

ABSTRACT: Single crystals of octa-deca-nickel dodeca-germanide were grown by chemical transport reaction. The inter-metallic compound crystallizes in a superstructure of the hexa-gonal NiAs type (B8 type). All atoms in the asymmetric unit lie on special positions except one Ni atom (two Ni atoms have site symmetry -6.. and another one has site symmetry .2. while the Ge atoms have site symmetries 32., m.. and 3..). In the structure, the Ni atoms are arranged in 11- or 13-vertex polyhedra (CN = 11-13). The coordination polyhedra of the Ge atoms are bicapped square anti-prisms (CN = 10) or 11-vertex polyhedra (CN = 11). The structure exhibits strong Ge?Ni inter-actions, but no close Ge?Ge contacts are observed. The Ni atoms with CN = 13 form infinite chains along [001] with an Ni-Ni distance of 2.491?(2)?Å.

SUBMITTER: Kars M 

PROVIDER: S-EPMC4350741 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature